What is structured data markup?

Structured data markup is code on a page that tells search engines what the page is about. Google calls structured data a standardized format for providing information about a page and classifying the page content. It matters because engines read it to display search results in a specific and much richer way, called rich results or rich snippets.

Structured data in simple terms

To a machine, a page of text is unstructured. It can read the words, but it has to guess which number is the price and which name is the author. Structured data refers to data that is organized, while unstructured data is unorganized data. Markup adds the labels. By structuring data, you disambiguate information to search engines, helping them to serve better information to searchers.

Why add structured data to a page?

The case for it is about how your result looks and how many people click it. Google's own documentation lists what sites saw after adding it:

• Rotten Tomatoes measured a 25% higher click-through rate for pages enhanced with structured data.
• The Food Network converted 80% of their pages to enable search features and saw a 35% increase in visits.
• Rakuten found that users spend 1.5x more time on pages that implemented structured data.
• Nestlé measured an 82% higher click through rate for pages that show as rich results.

Does it improve rankings?

None of those numbers is about ranking position. They measure clicks, visits and time on page, and the sources above make no claim that markup moves a page up. Add it so engines understand the page and can show it richly, not for a jump in position.

How it works: vocabulary and format

Markup has two parts: the words and the syntax. The words come from Schema.org. Most Search structured data uses schema.org vocabulary. Schema.org was founded by Google, Microsoft, Yahoo and Yandex, and its vocabularies cover entities, relationships between entities and actions. It is widely used: as of 2024, over 45 million web domains markup their web pages with over 450 billion Schema.org objects.

The syntax is one of three formats, and Schema.org vocabulary can be used with all of them:

Google recommends using JSON-LD in most cases because it is the easiest format to implement and maintain. It sits in its own block, so you can change it without touching the visible HTML.

An example

This page carries FAQPage markup in JSON-LD, built from the questions at the bottom. Trimmed to one question, it looks like this:

{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [{
    "@type": "Question",
    "name": "What is structured data in simple terms?",
    "acceptedAnswer": {
      "@type": "Answer",
      "text": "Labels in a page's code that tell search engines what each part of the page is."
    }
  }]
}

The question and answer are the ones a visitor reads below. Anything in the markup should also be on the page.

Which pages gain most

There are structured data formats for books, reviews, movies, and products. Pages about one clear thing with clear properties (a recipe, a product, a set of questions and answers) have the most to label. A general blog post has less, though Article markup still says who published it and when.

How to check yours

View the source of a page and search for application/ld+json to find its JSON-LD. Then run the URL through a structured data testing tool, which lists the types it found and any errors. If you build with Claude Code or Codex, Shipfound checks the live site for missing structured data and ships the markup as a pull request.

Common mistakes

• Markup that says something the page does not. Describe what a visitor can see.
• Markup on the wrong page. Structured data is coded using in-page markup on the page that the information applies to, so a product's details belong on that product's page.
• Avoiding JSON-LD because a framework adds it with JavaScript. Google can read JSON-LD data when it is dynamically injected into the page's contents.
• Inventing your own types. Use the schema.org vocabulary the engines read.

How AI search reads markup next to text, images and video is in how AI crawlers handle structured data.

Frequently asked questions

What is structured data in simple terms?

Labels in a page's code that tell search engines what each part of the page is.

What is an example of structured data?

A recipe page that marks up its ingredients, preparation time and calories, or a product page that marks up its price and reviews. Structured data can tell search engines all of these.

Can you give me an example of schema markup?

The JSON-LD block above uses the schema.org FAQPage type. A Product block with a name, a price and reviews is another common one.

What is the difference between structured data and schema markup?

Structured data is the general idea of labeling a page's content in a standard format. Schema markup is structured data written in the schema.org vocabulary, which is the vocabulary used by the big search engines. In practice people use the two terms for the same thing.